-LRB- CNN -RRB- -- On the morning of August 5 , my uncle , Satwant Singh Kaleka , and five other innocent people were gunned down in our place of worship , the Sikh Temple in Oak Creek , Wisconsin . The tragedy left us wondering what it will take to stem the growing tide of hate crimes and violence plaguing our nation .

The Senate is holding a hearing on domestic terrorism on Wednesday , and I hope it will do more than simply offer my community a chance to vent frustrations and appeal for sympathy . My hope is that the hearing provides an opportunity for Americans to come together and identify solutions .

We need to be aware that the killings in Oak Creek , as well as recent attacks on the mosque in Joplin , Missouri , and more than a dozen others across the country , will continue if we turn a blind eye to domestic terrorism . It is a significant , growing threat to our safety and freedom as Americans .

We must ensure our safety within our own borders before we can hope to address violence elsewhere . According to the FBI , between 1980 and 2001 , two-thirds of terrorist attacks in America were carried out by non-Islamic American extremists . That rose to 95 % between 2002 and 2005 .

A recent study by the New America Foundation found that non-Islamic U.S. citizens were behind 10 attacks from 9/11 through 2011 , while jihadists carried out four . During the same time , 11 white supremacist , anarchist or right-wing extremists were caught with biological or chemical weapons -- anthrax , cyanide , ricin or sarin -- and four attempted to acquire them . The study found not a single jihadist terrorist possessed or tried to acquire chemical or biological weapons .

Eleven years after 9/11 , who are the terrorists ?

Even more worrying is that radical right groups are growing explosively , according to the Southern Poverty Law Center . Yet appallingly , our government has not only failed to increase its efforts to monitor this threat , but in 2009 , it decreased efforts , leaving only one staffer in the Department of Homeland Security 's domestic terrorism unit , according to Daryl Johnson , a senior domestic terrorism analyst from 2004 to 2010 .

We know there are at least 1,018 domestic hate groups in the United States today , many of which promote and explicitly call for violence against those of a different skin color , religion or ideology . How long can we keep our heads in the sand , and how long must we sit by as more innocent people die because a person decides that he wo n't tolerate the cultural or religious diversity of our nation -- our melting pot ?

A coward killed my uncle . A coward , not because he went into a place of worship and took the lives of six unarmed people , and not because he took his own life rather than facing the consequences of his actions . He was a coward because he did n't have the courage to see the humanity of the people around him .

He -- like all terrorists -- killed people because they were not like him , because they were different . The reality is we are all different from one another , and that means we are all potential targets for such violence . This problem affects each and every one of us , so it 's imperative that we act decisively , and act now .

This is not a problem that is simply going to go away . The government agencies charged with defending our freedom and safety must make it a priority to fight terrorism not just abroad , but right here at home . And we as the citizens must rid ourselves of the hate speech and the xenophobia -- including Islamophobia -- that divides us . This is particularly true of our leaders .

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We can not give into the cowardice of prejudice . As the great Franklin Delano Roosevelt once said , `` We are a nation of many nationalities , many races , many religions -- bound together by a single unity , the unity of freedom and equality . '' Together we can -- together we must -- address this challenge by calling on our elected officials to do their duty : defend the safety and freedom we as all Americans cherish .

The opinions expressed in this commentary are solely those of Kanwardeep Singh Kaleka .

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Kanwardeep Kaleka : Sikh community optimistic about hearing on domestic terrorism

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Kaleka 's uncle was killed in the Sikh temple massacre carried out by American

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Kaleka : Homegrown terror groups are growing fast and present a real threat

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The government must make it a priority to fight terrorism at home , he writes